1. Field of the Invention
The present invention relates to a dust container for collecting dust such as toner to accumulate therein, and relates to an image forming apparatus that has the dust container, including a copying machine, a printer, a facsimile, a plotter and the like.
2. Description of the Related Art
In image forming apparatuses such as a copying machine, a cleaning unit removes post-transfer residual toner that is remaining on a photosensitive drum or an intermediate transfer belt after toner image is transferred onto a recording medium or an intermediate member. The toner is collected and accumulated in a waste-toner collecting container in an image forming process. Such waste-dust container includes a toner inlet connected to the cleaning unit, a toner conveying unit that conveys toner accommodated into the container, and a toner detector that detects a degree of toner accommodation, a filling rate, in the container. The waste-toner collecting container is replaced with a new one when the toner detector detects a state in which the container is fully filled with toner. For improving the user's convenience, the replacement operation would be preferably be much reduced, so that it is advisable a capacity of the container be as larger as possible.
However, when there is not much space in a height direction of a main unit of the image forming apparatus due to down-sizing, a form of the waste-toner collecting container becomes broader horizontally and smaller in a height direction inevitably. That is the reason why the container is likely to be formed in a flat shape, which is wide in the horizontal direction and short in the vertical direction.
In such a container shape, it is difficult to accumulate toner evenly therein, where toner can partially agglomerates. The toner detector is provided on a downstream side in a toner flow direction, where the toner detector detects a remaining amount of how much further toner can be accumulated in the cartridge. When toner accumulates around the toner detector in an agglomerated state, the toner detector detects a toner-filled state in the whole of the container, which shows a need of replacement even though the cartridge is of unfilled state, leading to user's inconvenience.
To solve a problem of blocking generation of waste-toner, a technique disclosed in Japanese Patent Application Laid-open No. H11-002947 is to fully replenish toner efficiently while preventing aggregation of toner contained in the cartridge preliminarily. It is disclosed that an eccentric cam is provided on a shaft of a screw that replenishes toner outside, a flat plate is reciprocated in a horizontal direction by the eccentric cam, and toner is conveyed by a reversed V-shaped inward-oriented protrusion formed on the flat plate integrally. However, when the conveying system is applied to the waste-toner collecting container, toner is likely to be accumulated around the toner detector in an agglomerated state, so that the problem of erroneous detection is not solved.
Such techniques are disclosed in Japanese Patent Application Laid-open Nos. H10-207202, H05-204281, and H06-118846 that a configuration for loosening toner that causes blocking. The proposed configuration includes a plate member that can reciprocate arranged in the waste-toner collecting container, a protrusion portion that advances into a toner inflow port so that the inflow toner is provided on the plate member, and the plate member reciprocated to loosen toner by the protrusion portion. In this configuration, a toner amount becomes maximum at a toner introductory portion of the waste-toner collecting container, and a movement amount of the toner is reduced according to a movement from the introductory portion, so that toner is not conveyed to a position where toner is detected by the toner detector. Therefore, such problem has not been solved that waste-toner near the introductory portion of the waste-toner collecting container is scattered to contaminate the inside of the apparatus.
With regard to this problem, to control waste-toner to be accumulated evenly, it is required to make a plurality of different toner flows that are different in direction at different positions at a horizontal plane inside the waste-toner collecting container. FIG. 14 is a sectional view for explaining a waste-toner collecting container used in related arts. FIG. 15 is a sectional view for explaining another waste-toner collecting container used in related arts. To satisfy this requirement, a configuration that toner agitating rods 16 are arranged so as to cover the whole area of a bottom face of a waste-toner collecting container 14, as shown in FIG. 14, and a configuration that many conveying screws 17 are arranged inside the waste-toner collecting container 14, as shown in FIG. 15 behave been proposed, for example.
However, in such related arts, a configuration for driving an agitating unit such as the toner agitating rods 16 or the conveying screws 17 becomes complicated, leading unavoidably expensive. This is because a complicated gear train is required for simultaneously rotating a plurality of agitating units in different directions.